Process of coating metals, alloys, or other materials with protective coats of metals or alloys.



F. A. VAUGHN.

PROCESS OF COATING METALS, ALLOYS, OR OTHER MATERIALS WITH PROTECTIVE COATS 0F METALS 0R ALLOYS.

APPLlCATlON FILED 0015,1917.

1 2381 108., Patented 001;. 8, 19L8.

INVENTOR v BY ATTORNEY ans "ear ion- FRANCIS A. VAUGHN, 0F MILWAC'KEE, WISCONSIN.

PROCESS OF COATING METALS, ALLOYS, OR OTHER MATERIALS WITH PROTECTIVE COATS OF METALS 0R ALLOYS.

Specification of Letters Patent. 7

Patented @ct. 8, 1918.

Application filed October 5, 1917. Serial No. 194,942.

To all whom it may concern:

Be it known that I, FRANCIS A. VAUGHN, a citizen of the United States, and resident of Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Processes of Coating Metals, Alloys, or other Materials with Protective Coats of Metals or Alloys, of which the following is a description, reference being had to the accompanying drawings, which are a part of this specification. The invention relates to a process of coating metals, alloys or other material with a protective or ornamental coating or coatings of metals or alloys.

One of the objects of this invention is to provide a process of coating materials with a metallic coating, more particularly of the non-corrosive varieties, in order to protect such materials from the elements or other destructive chemical and physical agents. Another object of the invention is to provide a process of coating metals or alloys with a coating of metals or alloys which.

are dissimilar from the metals or alloys to be coated by interposing a coating of electrolytic insulating material between the metal and. its metallic coating to prevent elec trolytic action between the dissimilar metals,

I am aware of the fact that numerous attempts have been made to coat materials with metals, either by electro-plating, galvanizing, metallizing or metal spraying, but in all of the above named processes numerous difliculties arise especially with certain metals or combinations of metals, that is, where a layer or layers of dissimilar metal are used as a coat, owing to the fact that in all such methods or processes the object to be coated usually must be thoroughly cleaned by expensive processes such as sand blasting, plckling, etc., and furthermore after the coating has been applied electrolytic or other corrosive action between the dissimilar metals causes reactions which sooner or later cause a failure of the coating, either chemically or physically. The importance of a successful solution of this. problem of the elimination of expensive processes of cleaning the materials and the prevention of electrolytic or other corrosive act on has long been recognized and the process hereinafter described has successfully solved the problem. i

My method consists in first coating ma- I trolytic insulating terial to be protected with a non-corrosive pr ming and binder coating and in addition sald coating being an electrolytic insulating coating. One material which has all the three properties of forming a priming, binder and electrolytic insulating coating is a solution of alkaline silicate, such as sodium silicate. The material to be protected is thus covered with av coating of a solution of alkaline silicate. This coating of alkaline silicate will cover and seal over the imperfections in the material and the pores of porous material and such detrimental objections as rust, corrosion, or other foreignmatter as. may exist if the surface to be we coated is a metal or alloy. In case the material to be coated is non-metallic the alkaline silicate serves as a priming and binder coating to form a clean binding surface, or matrix, but also forms an eleccoat to which the protective metal coatlng can be readily applied. The next step consists in applying the protective or ornamental coating of metal to the matrix coating. This is done by spraying, impacting or spreading the metal upon the coating. In spraying, the metal is discharged in hot impalpable particles moving with high velocity and these when directed-upon the preparedobject with the 86 plastic matrix coating-applied thereto penetrate said matrix while the spray is still plastic. The coating metal thus dovetails itself into the superficial pores of the matrix coating while the matrix coating binds the co metal coating to the object being coated. The

plastic matrix coating forms a better binder for the metal coating than can be obtained by spraying the metal directly onto the object to be coated and at the same time forms at an electrolytic insulating coat.

If the metal coating applied to the matrix coating is porous, which is generally the case,

' the object with the coatings applied is then treated so as to render the plastic matrix we coating hard and insoluble. When a solution of alkaline silicate is used as a matrix coating it is rendered insoluble by treating the coated object in such a way'as to precipitate out the silica as insoluble silicic acid. This may be done in any suitable manner and one way of doing it is to subject the coated object to the action of carbon dioxid either in a aseous or liquid form. This I may be done y placing the coated object in the air, but to hasten the hardening I refer to expose thecoated object to carbon ioxid or a carbon-dioxid-containing atmosphere to allow the carbon dioxid to penetrate through the pores of the metalcoatmg and thus render insoluble any exposed minute areas of the alkaline silicate coat.

15. In Fig. 1

In the drawings: Figure 1 is a sectional View showin the protective coating applied thereto in W 'ch the outer metallic coating is non-porous; Fig. 2 is a sectional view showing the protective coating apphed thereto in which the outer metallic coating is porous. I

the numeral '3 represents the material to be'coatecl, 4 the alkaline silicate coating, and 5 the non-porous metal coating and Fig. 2 shows the material 3 and coating 4: provided with a porous metal coating 6.

Itis understood, of course, that any combinationof alternate coats of alkaline silicate and metal may be used, the last named being either of one'kind or each successive coat of a difierent kind.j

In case the material to be covered is of a non-metallic character such as wood, glass or fiber, the priming and binding properties of the alkaline silicate are utilized to form a clean binding surface, or matrix, for the reception of the protective metal coating.

In case the material to be covered is a corrosive metal oralloy the binding and priming properties of the alkaline silicate are u ized to form a clean binding surface, or matrix, without the necessity of first cleaning the corrosive metal and where the metal coating isof a dissimilar character from that of the metal or alloy being coated the in a plastic condition and then electrolytic insulating property of the alka: line silicate provides for insulating the'two dissimilar metals from each other and thus prevents electrolytic or other corrosive action between them. 6 i I 1 What I claim as my invention is: 1. The herein described process of coating metal with a coatingof a dissimilar metal which consists in applying. a coating of binder and electrolytic insulating material material with a porous metal coating which consists in applying a matrix coating of plastic binder material over the material to be coated, spraying molten metal onto the matrix coating while said matrix coating is hardening the matrix coating. p

4. The herein described process of coating material with a porous metal coating which consists in applyinga matrix coating of a solution of alkaline silicate tothe material to be coated, spraying molten metal onto the matrix coating while said matrix coating is in a plastic condition, and then bringing the material socoated into the presence of carbon dioxid to harden said matrix coating.

In testimony whereof I aflix my si ature. FRANCIS A. VAU HN.- 

